OT: third party relay attack

Steffen Nurpmeso steffen at sdaoden.eu
Wed Jan 15 14:22:25 PST 2020

Jordan Geoghegan wrote in <a0b2e6b6-5710-f40b-c626-52b57eb3d362 at geoghega\
 |On 2020-01-10 03:04, Pierre Abbat wrote:
 |> My mailserver is being attacked by what looks like a botnet since \
 |> December 16
 |> at 6:07 (11:07 UTC). Many hosts all over the world are sending mail \
 |> purporting
 |> to be from many domains all over the world to a few domains in Russia. \
 |> Most of
 |> the IP addresses are blocked by uceprotect.net; a few are blocked \
 |> by other
 |> blocklists. A few are not blocked, but are rejected with "Relay access
 |> denied". The messages come at a rate of several per second.
 |> There are 133 emails stuck in leaf's mail queue, but they do not \
 |> appear to be
 |> related to this attack.
 |> Pierre
 |When dealing with spam, there is no magic one size fits all solution. In 
 |order to mitigate spam, you'll need to come up with a multi-layered 
 |anti-spam solution.
 |  I'm not sure what Steffans issue with OpenSMTPD was, it sounds like he 
 |made himself an open relay. I've run OpenSMTPD for a while now and its 
 |been working wonderfully for me.

My issue was in 2017.  I ran OpenSMTPD for a few days before
2017-10-28.  Nice that it works for you.

|Der Kragenbaer,                The moon bear,
|der holt sich munter           he cheerfully and one by one
|einen nach dem anderen runter  wa.ks himself off
|(By Robert Gernhardt)

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